It is known to provide electromagnetic generators for generating power from a gas turbine engine. Such generators can be housed within an engine structure such as a bearing housing. Such an arrangement offers advantages in terms of efficient packaging of engine components, but also poses new challenges, particularly in terms of maintenance.
In particular, the size and weight of electrical the rotors and stators of electrical machines makes removal and installation for maintenance and replacement difficult to carry out by hand. These difficulties are compounded by the magnetic forces produces between the stator and rotor when they are translated relative to each other.
Electrical machines housed within an engine structure such as a bearing housing may also experience relatively high temperatures in use, and so require a coolant system to provide a coolant flow through at least the stator. Such coolant systems also add further weight and complexity to the engine, and generally require an additional housing or casing in order to separate the coolant flow from the oil contained within the bearing housing.
The present invention seeks to address these issues.